An improved ZC-ZVS PWM DC-DC converter with a saturable inductor

This paper proposes an improvement in the buck ZC-ZVS PWM power converter. This is achieved by changing the auxiliary switch position, which reduces significantly its rating power. By employing a saturable inductor, the maximum voltage stress across the main switch becomes practically constant and independent of the load current. The load range is extended, maintaining soft switching commutation for all active devices. A boost ZC-ZVS PWM power converter derived from the buck ZC-ZVS PWM circuit is presented. The operating principles of both the proposed buck and boost topologies are described and confirmed by simulation results